- Copy stable/10@296371 to releng/10.3 in preparation for 10.3-RC1
builds.
- Update newvers.sh to reflect RC1.
- Update __FreeBSD_version to reflect 10.3.
- Update default pkg(8) configuration to use the quarterly branch.

Approved by: re (implicit)

MFC r282739:
ctf_add_type(): when looking up an integer or floating point type in the
list of pending dynamic type definitions, a match on the type name is not
sufficient - we need to compare the type encodings as well. For example,
bitfields have their own distinct type definitions which share the name of
the underlying integer type, and these types aren't generally
interchangeable.

This bug was causing the following libdtrace error when attempting to trace
the th_flags member of a struct tcphdr:
cg: bad field: off 104 type <32877> bits 539620016

MFC r279862:
Fix a possible infinite loop in ctf_discard().

MFC r279864:
Use CTF_TYPE_TO_INDEX when comparing type indices to the dynamic type
threshold.

MFC r279869:
If the destination container contains only a forward declaration for the
input type in ctf_add_type(), search its dynamic type list before adding
a new type.

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFV r254422:

Illumos DTrace issues:
3089 want ::typedef
3094 libctf should support removing a dynamic type
3095 libctf does not validate arrays correctly
3096 libctf does not validate function types correctly

This commit was generated by cvs2svn to compensate for changes in r178525,
which included commits to RCS files with non-trunk default branches.

Vendor import of DTrace support files from OpenSolaris.